Time Warner Cable Inc. Internet users soon will have to watch their downloads more closely.

The cable company has tapped San Antonio as one of its first markets to charge varying rates depending on how much data you use, instead of a flat fee.

It would be a first for the city.

Time Warner this month will begin collecting information on its customers' Internet usage, and will implement the new billing format late this summer.

The metering works like cell phone plans, where users will pay a certain price for their allotted data plan, but will have to pay extra if they go over their limit.

Plans will range from $29.95 to $54.90 per month with download caps of 5, 10, 20 and 40 gigabytes, according to a BusinessWeek.com article posted March 31.

Time Warner is considering adding a super tier of 100 gigabytes, according to Melissa Sorola, Time Warner's regional director of communications, who released a statement via her Twitter account.

The company declined to discuss prices.

A high-definition movie uses about 8 gigabytes of data, according to BusinessWeek.

For Time Warner users, every gigabyte over your limit will cost an extra $1.

The move is geared mostly toward heavy Internet users.

“A very small percentage of users can at times use up a large majority of the bandwidth system,” said Le Keough, a telecom analyst for Frost Bank. “I think for the majority of people, it's a nonissue.”

Those heavy users, who account for just 5 percent of all customers, use up to half of Time Warner's total bandwidth.

But if these metering moves do limit access for average users, “I guarantee you the FCC will get involved,” Keough added.

One concern is whether consumers are able to accurately monitor their downloading.

“When I'm on the cell phone, it's easy to know how many minutes and text messages I'm racking up,” Keough said. “When you're on the Internet, you have no idea about bandwidth.”

Time Warner's Sorola said that when the metering starts, customers will have a gauge that lets them track their consumption. She said customers' bills won't automatically increase, and that they will have a three-month grace period to monitor their usage before bills hit.

Time Warner also plans to use metering in Austin; Greensboro, N.C.; and Rochester, N.Y.

The company, which has more than 8 million customers nationwide, has been testing the concept in Beaumont during the past several months.

Of the 10,000 broadband customers enrolled, about 14 percent went beyond their cap and paid an average of $19 extra per month, according to BusinessWeek. Customers are notified when they reach 70 percent of their cap.

AT&T Inc., Time Warner's primary competitor in San Antonio, in November 2008 began tests of bandwidth caps of 60-150 gigabytes per month in Reno, Nev.

Users receive a notice when they've reached 80 percent of their capacity, and after a grace period are charged $1 per gigabyte over the cap.

GVTC Communications, which competes with Time Warner in North San Antonio and the Hill Country, doesn't have a tiered program and “continues to monitor all trials and launches of metered Internet access and continues to evaluate our options,” said Tom Zanoli, Internet product manager with the company.